Movable barriers of various kinds are known in the art. These include pivoting barriers such as, but not limited to, gates and carriage house garage doors of various kinds that pivot at one end thereof with respect to a support component. It is also known to employ a barrier operator (such as, but not limited to, a linear actuator) to control the automatic movement of the pivoting barrier. Such an approach can serve, for example, to permit the automatic opening and closing of the pivoting barrier.
It is known that an operator such as a linear actuator should be coupled such that the linear actuator is usually not parallel to the barrier itself. Such a configuration ensures that the linear actuator is actually able to exert the desired influence upon the barrier. It is also known to change the speed and/or acceleration at which the linear actuator retracts or extends in order to appropriately control the speed at which the barrier itself moves. Unfortunately, barrier speeds (as well as other operational physicalities such as experienced forces) at a given actuator speed of acceleration can vary dramatically with respect to the physical dimensions of the installation (for example, to a large extent, the speed of the barrier (or the forces being experienced by the barrier) at any given moment comprises a function of the angle between the barrier and the linear actuator arm). This variability is dynamic and can and will change over the course of the barrier's path of movement.
Accordingly, as great unpredictability can exist with respect to the physical dimensions that can result with respect to a given installation setting, corresponding significant uncertainty exists with respect to the actual resultant speeds a given pivoting barrier will experience through its path of travel. This, in turn, can lead to end user dissatisfaction, maintenance issues, operating difficulties, and so forth.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.